ABSTRACT
Objective@#To investigate the health effects of air pollution on elementary school students with the indicator of absenteeism caused by respiratory symptoms and diseases, and to provide a reference for improving their physical health.@*Methods@#Absenteeism, air pollutants, and meteorological data during Sep. 2015 to Jun. 2017 in Pudong, Shanghai were collected. Generalized additive model was used to estimate the effects of air pollution on students’ absenteeism caused by respiratory symptom and diseases, time trends, day of week and meteorological factors were controlled.@*Results@#Totally 47 723 person-days of elementary school students’ absenteeism caused by respiratory symptoms and diseases were recorded during Sep.2015 to Jun. 2016 in Pudong, Shanghai, and the absenteeism rate was 0.07%. The PM2.5 concentration on lag0 and SO2 concentration on lag2 showed the most significant effects, the elementary school students’ absenteeism raised for 1.43% (95%CI=0.25%~2.62%)and 6.79% (95%CI=0.25%~13.32%) respectively with every 10 μg/m3 increment of PM2.5 and SO2.@*Conclusion@#Air pollution in Pudong new area have made a influence on the elementary school student’s respiratory symptoms and absenteeism, and the prevention work of air pollution should be strenghthened.
ABSTRACT
Objective To explore the repair result of full-thickness cartilage defects in diannan small-ear pig by bone mesenchymal stem cells (BMSCs) transferred with both transforming growth factor-β3(TGF-β3) and bone morphogenetic protein-2(BMP-2) gene mediated by adenovirus vector and combined with deminerized bone matrix (DBM). Methods 32 full-thickness defects from 16 knees of 8 pigs were randomly divided into 4 groups in the experiments. In group A, the animals′ lateral femoral condyle of right knee joint was repaired with DBM and BMSC infected with both Ad-TGF-β3 and Ad-BMP-2. In group B, the medial femoral condyle of right knee joint was repaired with DBM and BMSC without infection. In group C, the lateral femoral condyle of left knee joint was repaired with DBM. And the group D is control group. Morphology and histology were observed 2, 4, 8 and 12 weeks after operation. Results 12 weeks after operation, the whole defects were repaired in group A, HE staining showed typical cartilaginous structure in the repaired area. In group D, defects were not repaired but filled with fibrous tissue. The O′driscoll scores were 15.65 ± 0.11 (group A), 11.33 ± 0.22 (group B), 6.13 ± 0.15 (group C) and 5.08 ± 0.15 (group D). There was significant difference among the groups (P < 0.05). Conclusions The new type of tissue engineering scaffold that DBM combined with BMSCs transfected with both Ad-BMP-2 and Ad-TGF-β3 could induce cartilage regeneration and repair the defects.